Monitoring engine torque in the drive train of a vehicle allows the engine, the transmission and vehicle controls to utilize this information to modify engine output, transmission ratio as well as motor/generator speed or torque, in the case of a hybrid transmission. Known torque monitoring systems present a variety of challenges. For example, a mechanically-mounted strain gauge presents packaging challenges due to electronic wiring needed to interconnect the strain gauge with a control signal receiver and controller. Additionally, magnetorestrictive technologies used to sense torque have significant packaging issues and may be cost prohibitive.
A magnetorestrictive material having magnetic characteristics that change with a change in torque requires the use of a drive line shaft or other torque-transmitting component having a nickel content that is cost prohibitive both from a material and processing standpoint. Additionally, packaging of a pick-up component, such as wire brushes, that can relay the magnetic change of the shaft, is difficult and requires additional assembly time.